1. Field of the Invention
A locking differential is disclosed having a cylindrical drive rod and V-shaped drive grooves including planar faces that are arranged at an obtuse angle of about 120xc2x0 and meet in diametrically arranged junctures. Helical biasing springs are provided having end portions that are mounted within pockets contained in the opposed faces of the clutch members, which spring members are inserted in an axially compressed condition during assembly between the opposed faces of the clutch members via assembling slots that communicate with the outer circumferential surfaces of the clutch members.
2. Brief Description of the Prior Art
Locking differential are well known in the patented prior art as shown by the patents to Lewis U.S. Pat. No. 2,555,044, Schou U.S. Pat. Nos. 4,400,996, 4,498,355, and 4,640,143, and Zentmyer U.S. Pat. No. 5,413,015. In the Schou patents, it was proposed to provide a pair of annular friction pack assemblies for normally connecting the drive shaft with the pair of output shafts, respectively. Upon the occurrence of an overrunning condition in which the rotational velocity of one output shaft exceeds that of the other shaft, the friction pack associated with the overrunning shaft is disengaged, thereby to disconnect the overruning shaft to a free-wheeling condition. In the Zentmyer patent, it was proposed to retrofit a locking differential into the conventional differential casing of a four-wheel vehicle of the like, thereby to permit rugged off-road operation of the vehicle.
In the Valente Patent No. 5,727,430, which is assigned to the same assignee as the present invention, a locking differential is disclosed that is adapted to retrofit into an existing differential casing, such as the original equipment differential casing of a four-wheel drive vehicle or the like, through an access opening contained therein, said differential including a pair of annual friction packs for normally connecting a drive shaft with a pair of driven output shafts. Side gears splined to the output shafts are normally connected with a pair of clutch or coupler members driven by the drive shaft by the friction packs, respectively. The clutch members are biased apart by a plurality of spring biasing assemblies each including a locking pin and a collinearly arranged helical spring, the locking pin being slidably mounted at one end in a bore contained in one face of a first clutch member, said pin extending at its other end in an oversized bore contained in the opposing face of the other clutch member, thereby to permit limited relative angular displacement between the clutch members.
The present invention was developed to provide an improved locking differential that is more easily assembled, of less costly construction, and provides smoother more positive differential operation.
According to a primary object of the invention, a gearless differential is provided having opposed clutch members containing V-shaped drive grooves that receive a cylindrical drive pin that is carried by the differential housing. The faces of the V-shaped groove are planar and are arranged to provide line-to-line contact with the drive rod.
According to another object of the invention, the clutch members are normally biased apart by a plurality of helical springs arranged longitudinally between the adjacent faces of the clutch members. The ends of the helical springs are received in opposed pockets contained in the opposed faces of the clutch members. Radially extending assembly slots are provided in the outer circumferential surfaces of the clutch members, thereby to permit introduction of the springs, when in an axially compressed condition, between the faces of the clutch members.